Roger Federer
Roger Federer has made the best start to a season since 2006 and has already picked up two titles Getty

Todd Woodbridge has revealed Roger Federer's main concern prior to the start of the 2017 season as he was making his comeback from a six-month injury absence.

The Swiss ace has made the best start to a season since 2006 and is currently on a 13-1 win-loss run which includes picking up titles at the Australian Open and most recently at the BNP Paribas Masters in Indian Wells.

The 35-year-old has surprised himself with his start after expecting to struggle following a six-month layoff owing to a knee injury. Prior to the first Grand Slam of the year, the former world number one's last ranking tournament was at Wimbledon in 2016.

He made his comeback at the Hopman Cup playing alongside Belinda Bencic before arriving in Melbourne for the first major tournament of the year. Woodbridge, a 16-time Grand Slam men's doubles winner, revealed that Federer's main concern was how his body would react to regular competition.

''He made an interesting comment to me at a function we did prior to the Australian Open, his first true 'comeback' test,'' Woodbridge said, as quoted by tennisworldusa.org. ''He said 'one thing that I don't know is how my body is going to recover after each match. Given the time I have had off, and the injury, I have to wait and see.' At that point he was saying that the semifinals of the AO would be a good result.''

Federer surprised himself and everyone else by going all the way and winning his 18th Grand Slam title by beating four top 10 players along the way. He suffered a shock second round defeat at the Dubai Tennis Championships but responded by winning the first Master Series event of the season. The Swiss maestro said recently that he is way ahead of schedule in terms of his targets for the 2017 season.